What was found
PDX - FLT 1394 - AFTER TAKEOFF PDX, WHEN LANDING GEAR RETRACTED, NOSE LANDING GEAR RED LIGHT REMAINED ILLUMINATED. ACCOMPLISHED ABNORMAL PROCEDURES WITH SAME RESULTS. AIRCRAFT RETURNED TO PDX AND LANDED WITHOUT INCIDENT. REPLACED NOSE LANDING GEAR RETRACTION CYLINDER. ACCOMPLISHED LEAK CHECK AND NOSE LANDING GEAR RETRACTION CHECK WITH NO DEFECTS FOUND. SYSTEM GROUND CHECKED NORMAL OPERATION. (M)